Glow cathode rectifier



G. H OLST ET AL GLOW CATHODE RECTIFIER Dec. 28, 1926.

Filed July 28. 1923 aka/Mb, Wwm (9W Patented Dec. 28, 1926.

\ 1,612,438 PATENT OFFICE.

GILLES HOLST, WILLEM OTTD JULIUS, AND EKKO OOSTERHUIS, OF EINDHOVEN,

NETHERLANDS, ASSIGNORS TO NAAMLOOZE VIENNOOTSCHAP PHILIPS PENFABRIEKEN, OF EINDHOVEN, NETHERLANDS.

GLOEILAM- GLOW CATHODE RECTIFIER.

Application filed July 28, 1923, Seria1 No. 654,482, and in the Netherlands July 31, 1922.

The present invention relates to devices with one or more glow-cathode-rectifiers and has for its object to increase the life of the said rectifier-tubes by a particular" combina- 5 tion or connection of the devices.-

wire less unequal.

As a rule the life of glowcathode-rectitiers depends on that of the cathode for which a tungsten coilis frequently used. Consequently an increase of the life of the cathode constitutes at the same time a lengthening of the life of the tube.

Applicants have found that the relatively short life of the cathode is partly due to an unequal charge on the incandescent wire. This unequal charge occurs during that part of the period of the feeding alternating current during which the current rectifier passes through. In this lapse of time both the heating current and the current rectified (discharge current) flow through the incandescent wire,

In every point of the incandescent wire, the current flowing at a given moment is equal to the algebraic sum of the heating current and the discharge current. .The former is equal for all points of the incandescent wire but the latter varies from point to point. If therefore the current is rectified, the strength of the current in the wire different for diiierent points of same. The actions of the current in a given point of the wire from moment to moment accumulate to a resulting eflect manifesting itself by a certain heating. disintegration or more generally wear of the wire (in the said point) which might be causedquite as well by an imaginary efi'ect-ive current not varying with the time.

According to the invention it is possible by a correct choice of the temporary course of the. heating current relative to the disclnlrgc-current to make the effective values of the currents in the difi'erent points of the As the heating current is usually a normal alternating current, it

may be also said that according to the invention the inequality of the effective currents from point to point in the wire is decreased m by a correct regulation or choice of the phase of the heating current relative to the tempocan be relatively accurately indicated beforehand. If the discharge-current is imagined to be decomposed into a continuous current and several alternating currents the frequencies ofwhich are harmonics of the heating current frequency, there must be according to the invention a phase difference of substantially 90 between the heating current and the first harmonic of the dischargecurrent. The first harmonic of the discharge current is considered to be that alternating current component of the discharge current, which has the same frequency as the heating current.

When applying the principle of the, invention to an arrangement connected to a three-phase system, the object of the invention can be realized by a simple connection. The device is preferably provided with a set of star-connected anode-windings and a set of star connected windings supply ing current to the glowcathodes, the two star-points being connected together with the interposition of' a battery or other consumption apparatus, the anodes being connected to the free ends of the anode-windings and the lowcathodes to the free ends of the windings supplying current to the glowcathodes in such a manner that the incandescent wire of each tubeis connected to those windings the voltages of which are displaced in phase 120 and 240 respectively in relation to the voltages of the anode-windings to which the anodes are connected.

The accompanyingdrawings represent a particular embodiment. of the invention applied to a three-phase system. In the said drawings Figure 1 is a diagram of an arrangement according to the invention,

connection of the various apparatus.

In Figure 1 t t and 6 are the secondary windings of a transformer and t' I7 and t, are the secondary windings of another transformer. y and 9, refer to the three incandescent wires of three rectifying tubes the anodes of which are indicated by (1,, a and a a and g, belong to the same tube, likewise a, and {7 and also a and 9 The windings 25,, etc., etc., and 9,, etc. are as regards their direction illustrated as vectors.

As shown in the drawing," the two sets of windings t etc., and t',, etc., are star-eon nected and the two star-points are connected 7 candescent wire g, is connected to the free" ends of the windings t' and t,,.

9, considered as a vector is perpendicular to t, and the incadescent current through 9, is consequently displaced relatively to the voltage of the winding t As the first harmonicof the dischargecurrent can be considered to be in phase with the voltage of the winding t, it is apparent that the connection illustrated comes up to'the requirements of the present invention.

Figure 2 shows more fully a device according to the principle on which the device shown in F igure 1 is based.

-The primary windings 1, 2 and 3 vof a transformer are delta-co nnected whereas the two sets of secondary windings 4,65. 6, and 7, 8, 9 are star-connected. The regulable windings 4, 5 and 6 are connected to the anodes of the tubes 10, 11 and 12, whereas the incandescent-current windings 7, 8 and 9 are connected to the incandescent wires in accordance with the principle on which the device shown in Figure 1 is based.

The two star-points are .connected together with the interposition ofthe battery 15 to be charged, a regulating resistance 14 and an ammeter 13 for reading the continuous current.

It will be obvious to those skilled in the art that the broad principle of the inventidn may be applied in many other ways than herein described'and illustrated.

What we claim is 1. In a rectifying systeni, glow cathode Y rectifier, an alternating current-supplyijfor the cathode of said rectifier and analternating current supply for the dischar e within said rectifier, the said two supplles being substantially 90 degrees :outof phase.

2. In 'a rectifying system, comprising glow cathode rectifiers'three glow cathode rectlfiers each comprlslng an anode andv a glow cathode, at least (fne three phase transformer, said transformer being provided Witha set of star-connected anode windings and a set of star-connected cathode windings for supplying current to the glow cathodes, said cathode windings normally having electroniotive forces displaced 120 and 240 respectively in relation to the electromotit'e forces of the anode windings, a consumption.apparatus, the star points of said" windings being connected together through said consumption apparatus, the anodes of said rect-ifiers being connected to the free ends of said anode windings and said glow-cathodes being connected. to the free ends of the windings supplying current thereto in such a manner that in each of said rectifiers the glow-cathode of a particular rectifier is connected tothose windingsthe electromotive forces of which are displaced 120 and 240 respectively in relation tothe electromotive force of the anode winding to which the anode of the same rectifier is connected.

In testimony'whereof we afiix our signatures:

GILLES HOLST. WILLEM OTTO JULIUS. EKKO OOSTERHUIS. 

